Thousands of AT&T customers suffer mobile and internet service outages, which also affect emergency calls to 911. The incident had its epicenter in Houston, Chicago, Dallas, Los Angeles and Atlanta, according to the tracking site Downdetector.

Some Verizon and T-Mobile customers also reported outages. It is unclear what caused these service interruptions. The San Francisco Fire Department reported on its social media account landline. If that is not an option, please try contacting a friend or family member who is a customer of a different operator and asking them to call on your behalf.